<h1 id="toc_0">jQuery是什么？</h1>
<span>jQuery是对js的简化操作</span>
<pre><code class="language-javascript">&lt;script&gt;
// 查询
    var div = document.getElementsByTagName(&quot;div&quot;);
    var one = document.getElementsByClassName(&quot;one&quot;);
    var two = document.getElementById(&quot;two&quot;);
// 操作css
    div[0].style.backgroundColor = &quot;red&quot;;
    one[0].style.backgroundColor = &quot;yellow&quot;;
    two.style.backgroundColor = &quot;blue&quot;;
&lt;/script&gt;
</code></pre>
